If A: B = 2 : 5, B : C = 5 : 7, C : D = 4 : 9 and D = 472.5, then A is equals to:

56.5 56 52 60

60

A   :  D 2   :  5  5   :  7 4   :  9 40 : 315  ⇒ 8  :  63 Now, ⇒ D = 63R = 472.5 ⇒ 1R = 7.5 ⇒ Hence, A = 8R = 8 × 7.5 = 60